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1.
Drugs R D ; 24(2): 285-301, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38958918

RESUMEN

BACKGROUND: Pegfilgrastim-cbqv/CHS-1701 (UDENYCA®) (hereafter referred to as pegfilgrastim-cbqv) was approved in 2018 by the US Food and Drug Administration as a biosimilar for pegfilgrastim (Neulasta®) (hereafter referred to as pegfilgrastim). Both pegfilgrastim-cbqv and pegfilgrastim are conjugates of recombinant human granulocyte colony stimulating factor (r-metHuG-CSF) with a 20 kDa polyethylene glycol (PEG) indicated to decrease the incidence of infection, as manifested by febrile neutropenia, in patients receiving myelosuppressive anticancer drugs. The demonstration of analytical similarity for PEG-protein conjugates presents unique challenges since both the protein and PEG attributes must be characterized. OBJECTIVE: The current study demonstrates the analytical similarity of pegfilgrastim-cbqv and the reference product, pegfilgrastim. In addition to the physicochemical and functional characterization of the protein, the study assessed attributes specific to PEGylation including PEG size and polydispersity, site of attachment, linker composition, and PEGylation process-related variants. METHODS: The structural, functional, and stability attributes of pegfilgrastim-cbqv and pegfilgrastim were compared using state-of-the-art analytical methods. For the protein, the primary structure, disulfide structure, and secondary and tertiary structures were assessed using traditional protein characterization techniques such as mass spectrometry (MS), circular dichroism (CD), intrinsic fluorescence, and differential scanning calorimetry (DSC), as well as more advanced techniques such as two-dimensional (2D) nuclear magnetic resonance (NMR) and hydrogen deuterium exchange (HDX). For the PEG moiety, the site of attachment, occupancy, linker composition, size and polydispersity were compared using mass spectrometry (both intact and after endoprotease digestion), multiangle light scattering detection (MALS), and Edman degradation. Purity assessments included the assessment of both protein variants and PEGylation variants using chromatographic and electrophoretic analytical separation techniques. The functional similarity between pegfilgrastim-cbqv and pegfilgrastim was compared using both a cell-based bioassay and surface plasmon resonance (SPR). The degradation rates and stability profiles were compared under accelerated and stressed conditions. RESULTS: Biosimilarity was demonstrated by a thorough assessment of physiochemical and functional attributes, as well as comparative stability, of pegfilgrastim-cbqv relative to pegfilgrastim. These studies demonstrated identical primary structure and disulfide structure, highly similar secondary and tertiary structure, as well as functional similarity. The impurity profile of pegfilgrastim-cbqv was comparable to that of pegfilgrastim with only minor differences in PEGylation variants and a slight offset in the PEG molar mass. These differences were not clinically relevant. The degradation profiles were qualitatively and quantitatively similar under accelerated and stress conditions. CONCLUSION: The structural, functional, and stability data demonstrate that pegfilgrastim-cbqv is highly similar to the reference product, pegfilgrastim.


Asunto(s)
Biosimilares Farmacéuticos , Filgrastim , Polietilenglicoles , Filgrastim/química , Polietilenglicoles/química , Biosimilares Farmacéuticos/química , Humanos , Proteínas Recombinantes/química
2.
J Alzheimers Dis ; 91(3): 999-1006, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36530088

RESUMEN

BACKGROUND: Strength and mobility are essential for activities of daily living. With aging, weaker handgrip strength, mobility, and asymmetry predict poorer cognition. We therefore sought to quantify the relationship between handgrip metrics and volumes quantified on brain magnetic resonance imaging (MRI). OBJECTIVE: To model the relationships between handgrip strength, mobility, and MRI volumetry. METHODS: We selected 38 participants with Alzheimer's disease dementia: biomarker evidence of amyloidosis and impaired cognition. Handgrip strength on dominant and non-dominant hands was measured with a hand dynamometer. Handgrip asymmetry was calculated. Two-minute walk test (2MWT) mobility evaluation was combined with handgrip strength to identify non-frail versus frail persons. Brain MRI volumes were quantified with Neuroreader. Multiple regression adjusting for age, sex, education, handedness, body mass index, and head size modeled handgrip strength, asymmetry and 2MWT with brain volumes. We modeled non-frail versus frail status relationships with brain structures by analysis of covariance. RESULTS: Higher non-dominant handgrip strength was associated with larger volumes in the hippocampus (p = 0.02). Dominant handgrip strength was related to higher frontal lobe volumes (p = 0.02). Higher 2MWT scores were associated with larger hippocampal (p = 0.04), frontal (p = 0.01), temporal (p = 0.03), parietal (p = 0.009), and occipital lobe (p = 0.005) volumes. Frailty was associated with reduced frontal, temporal, and parietal lobe volumes. CONCLUSION: Greater handgrip strength and mobility were related to larger hippocampal and lobar brain volumes. Interventions focused on improving handgrip strength and mobility may seek to include quantified brain volumes on MR imaging as endpoints.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Anciano , Actividades Cotidianas , Fuerza de la Mano , Encéfalo/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico por imagen , Hipocampo
3.
Glob Chang Biol ; 28(11): 3515-3536, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35293658

RESUMEN

Offshore platforms, subsea pipelines, wells and related fixed structures supporting the oil and gas (O&G) industry are prevalent in oceans across the globe, with many approaching the end of their operational life and requiring decommissioning. Although structures can possess high ecological diversity and productivity, information on how they interact with broader ecological processes remains unclear. Here, we review the current state of knowledge on the role of O&G infrastructure in maintaining, altering or enhancing ecological connectivity with natural marine habitats. There is a paucity of studies on the subject with only 33 papers specifically targeting connectivity and O&G structures, although other studies provide important related information. Evidence for O&G structures facilitating vertical and horizontal seascape connectivity exists for larvae and mobile adult invertebrates, fish and megafauna; including threatened and commercially important species. The degree to which these structures represent a beneficial or detrimental net impact remains unclear, is complex and ultimately needs more research to determine the extent to which natural connectivity networks are conserved, enhanced or disrupted. We discuss the potential impacts of different decommissioning approaches on seascape connectivity and identify, through expert elicitation, critical knowledge gaps that, if addressed, may further inform decision making for the life cycle of O&G infrastructure, with relevance for other industries (e.g. renewables). The most highly ranked critical knowledge gap was a need to understand how O&G structures modify and influence the movement patterns of mobile species and dispersal stages of sessile marine species. Understanding how different decommissioning options affect species survival and movement was also highly ranked, as was understanding the extent to which O&G structures contribute to extending species distributions by providing rest stops, foraging habitat, and stepping stones. These questions could be addressed with further dedicated studies of animal movement in relation to structures using telemetry, molecular techniques and movement models. Our review and these priority questions provide a roadmap for advancing research needed to support evidence-based decision making for decommissioning O&G infrastructure.


Asunto(s)
Ecosistema , Peces , Animales , Invertebrados , Larva , Océanos y Mares
4.
Am J Clin Nutr ; 111(1): 170-177, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31711104

RESUMEN

BACKGROUND: Antioxidant nutrients such as the polyphenols in pomegranate juice may prevent neuronal damage from the free radicals produced during normal metabolism. Previous research in animals and a short-term clinical trial in middle-aged and older adults support the potential memory benefits of pomegranate juice; however, the long-term effects of pomegranate juice consumption on cognition have not been studied. OBJECTIVE: In this study, we investigated the long-term effect of pomegranate juice on memory in nondemented middle-aged and older adults. METHODS: We performed a 12-month, randomized, double-blind, placebo-controlled trial of pomegranate juice in middle-aged and older adults. Two hundred and sixty-one subjects (aged 50-75 y) were randomly assigned to consume pomegranate juice [8 oz (236.5 mL) per day] or a placebo drink (8 oz, matched constituents of pomegranate juice except for pomegranate polyphenols). Memory measures [Brief Visuospatial Memory Test-Revised (BVMT-R) and Buschke Selective Reminding Test (SRT)] were assessed at 6 and 12 mo and analyzed using a mixed-effects general linear model. RESULTS: Twenty-eight subjects in the pomegranate juice group and 33 subjects in the placebo group dropped out before completing the study. Baseline variables in the 98 pomegranate juice and 102 placebo group subjects who completed the study did not differ significantly. Group by time interaction was statistically significant for BVMT-R Learning (F[2, 257]= 5.90, P = 0.003; between-group effect size [ES] = 0.45): the change within the pomegranate group was not significant (ES = 0.15), whereas the placebo group showed a significant decline (ES = -0.35). Changes in the other BVMT-R scores as well as the SRT measures were not significantly different between groups. CONCLUSIONS: Daily consumption of pomegranate juice may stabilize the ability to learn visual information over a 12-mo period. This trial was registered at clinicaltrials.gov as NCT02093130.


Asunto(s)
Envejecimiento/metabolismo , Jugos de Frutas y Vegetales/análisis , Memoria , Granada (Fruta)/metabolismo , Anciano , Envejecimiento/psicología , Cognición , Método Doble Ciego , Femenino , Frutas/química , Frutas/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Granada (Fruta)/química
5.
Am J Geriatr Psychiatry ; 20(6): 514-23, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21765343

RESUMEN

CONTEXT: Age-related memory decline affects a large proportion of older adults. Cognitive training, physical exercise, and other lifestyle habits may help to minimize self-perception of memory loss and a decline in objective memory performance. OBJECTIVE: The purpose of this study was to determine whether a 6-week educational program on memory training, physical activity, stress reduction, and healthy diet led to improved memory performance in older adults. DESIGN: A convenience sample of 115 participants (mean age: 80.9 [SD: 6.0 years]) was recruited from two continuing care retirement communities. The intervention consisted of 60-minute classes held twice weekly with 15-20 participants per class. Testing of both objective and subjective cognitive performance occurred at baseline, preintervention, and postintervention. Objective cognitive measures evaluated changes in five domains: immediate verbal memory, delayed verbal memory, retention of verbal information, memory recognition, and verbal fluency. A standardized metamemory instrument assessed four domains of memory self-awareness: frequency and severity of forgetting, retrospective functioning, and mnemonics use. RESULTS: The intervention program resulted in significant improvements on objective measures of memory, including recognition of word pairs (t([114]) = 3.62, p <0.001) and retention of verbal information from list learning (t([114]) = 2.98, p <0.01). No improvement was found for verbal fluency. Regarding subjective memory measures, the retrospective functioning score increased significantly following the intervention (t([114]) = 4.54, p <0.0001), indicating perception of a better memory. CONCLUSIONS: These findings indicate that a 6-week healthy lifestyle program can improve both encoding and recalling of new verbal information, as well as self-perception of memory ability in older adults residing in continuing care retirement communities.


Asunto(s)
Envejecimiento/psicología , Cognición , Estilo de Vida , Trastornos de la Memoria/rehabilitación , Memoria , Educación del Paciente como Asunto/métodos , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Dieta , Ejercicio Físico , Femenino , Conductas Relacionadas con la Salud , Humanos , Masculino , Pruebas Neuropsicológicas , Estudios Prospectivos , Reconocimiento en Psicología , Estrés Psicológico/prevención & control
6.
Salud(i)ciencia (Impresa) ; 16(2): 148-155, jun. 2008.
Artículo en Español | LILACS | ID: biblio-836544

RESUMEN

En los últimos años se han dado controversias importantes acerca de los efectos de la estrogenoterapia sustitutiva y, en términos más generales, la terapia de reemplazo hormonal (TRH) sobre la enfermedad de Alzheimer (EA) y otras enfermedades neurodegenerativas. Esta revisión presenta algunos de los hallazgos y aportes más recientes en estudios de ciencias básicas, ensayos clínicos aleatorizados e investigación epidemiológica relacionada con los efectos neuroprotectores potenciales de la TRH en EA, demencia asociada con VIH y enfermedad de Parkinson (EP). Ha ido ganado más adeptos la convicción acerca de la capacidad de la TRH de reducir el riesgo de EA y mejorar el funcionamiento cognitivo de las mujeres posmenopáusicas, sobre todo cuando se consideran también las limitaciones del Women’s Health Initiative Memory Study de 2002. También se está prestando mayor atención a los efectos sintomáticos y neuroprotectores de la TRH en el tratamiento de la EP, así como al papel de la TRH como estrategia novedosa en la prevención y el tratamiento de la demencia asociada con VIH. Existen limitaciones importantes en la investigación actual, pero también razones convincentes para volver a examinar el modo en que algunas formas de TRH pueden ayudar a preservar las capacidades cognitivas en mujeres posmenopáusicas y evitar las enfermedades neurodegenerativas.


In the past several years, there has been a significant amount of controversy about the effects of estrogen replacement therapy (ERT) and, more generally, hormonereplacement therapy (HRT) on Alzheimer’s (AD) and otherneurodegenerative conditions. This review presents some of the more recent findings and developments in basicscience studies, randomized clinical trials, and epidemiological research regarding the potential neuroprotective effects of HRT in AD, HIV-associated dementia (HAD), and Parkinson’s disease (PD). Increased support iscontinuing to emerge for HRT’s ability to reduce the riskof AD and improve the cognitive functioning ofpostmenopausal women, particularly when consideredalongside the limitations of the 2002 Women’s HealthInitiative Memory Study. Greater attention is also beinggiven to the symptomatic and neuroprotective effects ofHRT in the management of PD, as well as the role of HRTas a novel strategy in the prevention and treatment of HAD. There are important limits to the existing research, but there are also persuasive reasons for reexamininghow some forms of HRT may help preserve cognitiveabilities in post-menopausal women and stave off neurodegenerative diseases.


Asunto(s)
Enfermedad de Alzheimer , Estrógenos , Demencia Frontotemporal , Terapia de Reemplazo de Hormonas , Enfermedad de Parkinson , VIH , Posmenopausia
7.
J Am Soc Nephrol ; 15(7): 1744-55, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15213262

RESUMEN

Cystic kidney disease has been linked to mutations in the Invs gene in mice with inversion of embryonic turning (inv/inv) and the INVS (NPHP2) gene in infants with nephronophthisis type 2 (NPHP2). The inv mouse model features multiorgan defects including renal cysts, altered left-right laterality, and hepatobiliary duct malformations transmitted in an autosomal recessive manner. Affected mice usually die of renal and liver failure by postnatal day 7. Although cardiopulmonary and liver anomalies have been carefully detailed, renal cysts have yet to be fully characterized in inv/inv. By use of three-dimensional visualization by two-photon microscopy, this study provides the first comprehensive analysis of in situ cyst formation and progression in inv/inv kidneys. At embryonic day 15, there is dilatation of Bowman's capsule followed temporally by corticomedullary cysts involving collecting ducts, proximal tubules, and thick ascending limbs. Collecting ducts of newborn inv/inv mice are uniformly and diffusely cystic from medulla to cortex, with normal diameters found only at their most proximal tips. Proximal tubules form fusiform cysts that alternate with segments of normal or narrowed caliber along torturous convolutions. Because defective cilia have been linked to situs inversus and cystogenesis, we examined inv/inv cilia by scanning and transmission electron microscopy. The former detected monocilia of expected length in cystic collecting ducts and proximal tubules; the latter demonstrated the usual 9 + 2 pattern in respiratory cilia. The inv mutant mouse has renal cysts resembling infantile NPHP2 and will provide broader insight into the role cilia play in renal cystogenesis.


Asunto(s)
Quistes/patología , Enfermedades Renales/genética , Enfermedades Renales/patología , Factores de Transcripción/genética , Animales , Peso Corporal , Heterocigoto , Homocigoto , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Riñón/ultraestructura , Túbulos Renales/metabolismo , Ratones , Ratones Transgénicos , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Mutación , Tamaño de los Órganos , Fenotipo , Fotones , Factores de Tiempo
8.
J Food Prot ; 65(6): 1008-15, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12092714

RESUMEN

The effects of different humectants (sodium chloride, sucrose, and glycerol) on the growth of and compatible solute (glycine betaine, proline, and carnitine) uptake by the osmotolerant foodborne pathogen Staphylococcus aureus were investigated. While growth in the presence of the impermeant humectants sodium chloride and sucrose induced the accumulation of proline and glycine betaine by cells, growth in the presence of the permeant humectant glycerol did not. When compatible solutes were omitted from low-water-activity media, growth was very poor in the presence of impermeant humectants. In contrast, the addition of compatible solutes had essentially no effect on growth when cells were grown in low-water-activity media containing glycerol as the humectant. Carnitine was found to accumulate to high intracellular levels in osmotically stressed cells when proline and glycine betaine were absent, making it a potentially important compatible solute for this organism.


Asunto(s)
Glicerol/farmacología , Staphylococcus aureus/crecimiento & desarrollo , Betaína/metabolismo , Transporte Biológico Activo/efectos de los fármacos , Cromatografía en Capa Delgada , Crioprotectores , Imagen por Resonancia Magnética , Concentración Osmolar , Presión Osmótica , Permeabilidad , Densidad de Población , Prolina/metabolismo , Cloruro de Sodio/farmacología , Staphylococcus aureus/metabolismo , Sacarosa/farmacología , Agua/metabolismo
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